1. Field of the Invention
The present invention relates to a semiconductor device. More specifically, the present invention relates to a spiral inductor for a semiconductor device.
2. Discussion of the Related Art
In order to generate inductance in the substrate of a semiconductor, semiconductor devices include inductors, which are generally formed from forming a metal wire into a spiral form. For example, in the configuration shown in FIG. 1, a metal wire 102 is formed into an inductor in a semiconductor substrate 100 by forming a spiral structure from a series of straight lines.
One difficulty in forming the spiral structure using a series of straight lines, however, is that polarization occurs at the edges of the metal wire, causing increased resistance in the inductor and a high parasitic capacitance between the metal lines. In particular, in configurations where the metal wire is formed directly on the semiconductor substrate, an eddy current may be generated on the semiconductor substrate, which impedes the operation of the any circuit, such as a transistor, which has been previously formed on the semiconductor substrate. Thus, one difficulty is that it is difficult to produce a high-quality inductor on the semiconductor substrate due to the loss caused by eddy currents or displace currents generated by the inductor of the current art.